Article handling device



May 2l, 1957 M. MAcoNEGHY ETAL "2,792,810

ARTICLE HANDLING DEVICE ATTORNEY May 21, 1957 M. MAcoNEGl-IY ETAL2,792,810

` ARTICLE HANDLING DEVICE:

Filed March ;l, 1954 2 Sheets-Sheet 2 lNvENToRs MILTON MACOMEGHY EARL F.WALTS By WW ATTORNEY ARTICLE HANDLING DEVICE Milton Maconeghy, Romulus,and Earl F. Walts, Union Springs, N. Y., assignors to Sylvania ElectricProducts Inc., a corporation of Massachusetts Application March 1, 1954,Serial No. 413,086

7 Claims. (Cl. 118-503) The present invention relates toarticle-handling devices, and particularly to operating mechanisms forimparting special motions to such article-handling devices. Theinvention is especially advantageous for lifting and spinning televisionpicture tubes during their manufacture to facilitate the application ofinternal conductive coatings to the tube envelopes.

The handling of television picture tubes has been a troublesome problem,particularly in mass production situations, since the tubes ordinarilyinclude fragile materials such as glass in their structure. The problemis complicated by the odd configuration of the body, which usuallyincludes an elongated, slender neck section for the support of anelectron gun. With the recent advent of large size picture tubes havingscreens as large as" 27" or 30 and weighing 40 pounds or more, thediiculties in transferring, lifting,`and holding the tubes for variousmanufacturing steps have become more pronounced. These operations oftennecessitate resort to specially designed, complex mounting chucks, eachcommensurate in size with a given picture tube, and necessitates theemployment of operators capable of lifting, positioning, and thenmanipulating the chuck locking arrangements. These as well as otherdisadvantages have established the need for simplitied apparatusfacilitating tube handling in a manner compatible with mass productionof picture tubes at relatively low unit cost.

One such handling situation occurs during picture tube production at thestation on the production line at which an internal coating of graphitein a colloidal suspension, referred to as aquadag, is applied toprescribed regions of the tube envelope. This coating step is ordinarilyaccomplished while holding` the tube envelope inverted at an angle ofapproximately 45 with respect to the horizontal. Thereafter, while thetube is spun about its longitudinal axis, an operator applies thecoating to the interior of the tube envelope by means of a handheld,elongated brush. Heretofore it has been necessary to employ manual laborto transfer the tube envelope from a conveyor to a downwardly inclinedchuck by which the envelope is received, held, and rotated during thecoating operation.

The present invention eliminates many of the above described handlingsteps by providing novel mechanisms for automatically lifting thevariously sized picture tubes from a support, transferring the picturetubes to a coating position, axially spinning the so-transferred picturetubes, and then returning the coated blanks to the support from whichthey had been taken.

ln accordance with one aspect ofthe invention, a lifting apparatus atthe production line coating station is'provided with a vacuum chuckwhich grips a picture tube blank with a suction force sufficient to holdit and to preclude inadvertent release by jarring, etc. The vacuum chuckis mounted for controlled movement away from the loading position atwhich the vacuum chuck grips the picture tube, to a coating position atwhich the'picture tube is angularly disposed, appropriate mechanismsbeing provided for spinning the picture tube while in the angularposition. Provision is made for return of the coated tube to theunloading position. As a specific feature, the picture tubes areinitially supported in inverted (neck down) condition on individualcradle-like supports which preferably form part of an automatic conveyorfor intermittently moving successive tubes into loading positionrelative to the vacuum chuck.

Once a given tube is in loading position at the coating station,mechanisms are provided for grasping the tube blank with the vacuumchuck and then moving the tube from the loading to the coatingpositions. The mechanism insures that the fragile depending neck of thecathode ray tube blank adequately clears the structure of the cradle andthat the tube is then properly positioned for convenient application ofthe coating by a hand positioned brush.

In accordance with a further aspect of the present invention, a liftingmotion for the vacuum chuck is obtained by the provision of structuresimparting compound movements to the vacuum chuck. The rate of turningduring a first interval of lift is selected to assure removal of thepicture tube without contact with the conveyor support, while the rateof turning during a second interval of lift is selected to obtain rapiddisplacement into the angularly olset coating position.

The above and still further features, objects, and advantages of thepresent invention will become apparent upon reference to the followingdetailed description of an illustrative embodiment when taken inconjunction with the accompanying drawings, in which:

Fig. 1 is a view in elevation, with parts broken away and shown insection, showing a cathode ray tube handling unit embodying features ofthe present invention, with the vacuum chuck or head in a loadingposition relative to a conveyor-supported picture tube, and with anintermediate position of the apparatus during travel away from theconveyor support illustrated by the broken lines;

Fig. 2 is a fragmentary view in elevation showing the supported picturetube in an intermediate position of clearance with respect to theconveyor support, the position of the tube while in the loading positionbeing illustrated by the broken lines; and,

Fig. 3 is an elevational view similar to Fig. 2 showing the picture tubeangularly odset and in position for the coating operation.

Referring now to the drawings, and particularly to Fig. 1, there isshown a combined lift and spinning station 10 arranged to receive thepicture tube blank P which is to be transported to the coating position.In the illustrative arrangement, the station 10 is associated with aconveyor 12 having tracks 13 along which a number of centrally aperturedcradle-like supports 12a carry individual picture tube blanks P with thepicture tube faces f uppermost and with the neck section n dependingwithin the general outline of the conveyor 12. The conveyor 12 may bepart of a production line having other cathode raytube processingstations, such as screen settling and drying stations in advance of thecoating station 10, and drying stations following the aquadag coatingstation. In the interests of simplicity and clarity, further details ofthe conveyor 12 will be omitted. -For the present purpose it suffices topoint out that the conveyor 12 may be periodically indexed in timedrelation to other operations, or under control of an operator, to lbringsuccessive picture tube blanks P into an appropriate position relativeto the handling apparatus at the coating station 10.

The article handling apparatus vat coating station 10 includes avertical frame or standard 16 arranged at yone side of the conveyor 12.A space 18 on the other side of the conveyor is kept free of equipmentso as to proaccanto U vide an operator-s station. The frame 16 of theillustrative embodiment is shown as having two vertical posts 16ainterconnected by cross bars 16h.

The frame 16 supports a combined lift and spinning head 20 which isarranged in overhanging relation to the conveyor 12 and is mounted formovement along a prescribed path, as will subsequently be described. Thecombined lift and spinning head Ztl supports a circular vacuum chuck 22(shown here in cross-section along a diameter) which is mounted forspinning about its axis on a hollow shaft 24. The combined lift andspinning head 2t) includes a box-like housing 26 having a front wall 27which supports the forward-projecting bearings 28, the bearings beingaligned to receive and support the yaxial vacuum chuck -drive shaft 24.

The vacuum chuck or work holder-22 embodies anged plate 23 anchored andherrnetically sealed to the hollow shaft 24 and an annular elastic ring25 mounted in an annular recess in plate 23. The ring 25, which may bemade of rubber or rother appropriate elastomer, may be provided with alower face shaped to conform with the curvature of the face f of thepicture tube. A partial vacuum is developed in the vacuum chuck 22 by asuitable pump and-vacuum reservoir located at the aquadaging station 10,the details of which are well known per se. For the present purposes, itsuces t-o point out that the external pump and reservoir, not shown, areconnected by supply line 29 to the hollow drive shaft 24, and so to thevacuum chuck 22. An appropriate control, such as the foot treadle 52 isplaced by the conveyor at the operator station 18 and controls theapplication of the vacuum to the supply line, and so to the vacuumchuck, at the will -of the operator. Although a manual system has beenshown for controlling operation of the vacuum chuck, it is to beunderstood that the application -of the required partial vacuum to thechuck may be initiated and terminated at predetermined intervals byappropriate mechanisms coordinated with the production line system. Fromthe foregoing description, it can be seen that when the combined liftingand spinning head 20 is in the tube-loading position of Fig. l and uponapplication of a partial vacuum to the chuck 22, the face of picturetube P will be gripped and held firmly by the chuck.

Subsequent to gripping of the picture tube P by the vacuum chuck 22, aspreviously described, the chuck 22 is moved from the tube-loading orpick-up position of Fig. 1, through the intermediate conveyor-clearanceposition of Fig. 2, into the angularly-oset coating position of Fig. 3.`A lift mechanism, generally designated by reference numeral 39, isinterconnected between the frame 16 and the combined lifting andspinning head 20 and serves to provide the special motion required. Ascan be seen from the relative positions lof the lift head 20 in Figs. land 2, the lift mechanism 30 rst displaces the vacuum chuck 22 and thepicture tube P along Ian arcuate path having a relatively gradualcurvature, so as to assure clearance of the depending section n from thecradle-like support 12a prior to angular offsetting of the picture tubeto the coating position of Fig. 3. As seen in Figs. 2 and 3, the liftmechanism 30 then rapidly rocks the picture tube from the clearanceposition of Fig. 2 to the angularly-otfset position of Fig. 3.

The lift mechanism 30 includes a bell crank lever or pivot arms 32a, 32bdisposed on `opposite sides of the drive housing 26. The pivot arms 32a,32b are pivoted ou main pivot shaft 3d which is arranged horizontallyand journaled between the upright posts 16a of the frame 16. The ends ofpivot arms 32a, 32b which are remote from the main pivot shaft 34 areconnected to the combined lifting and spinning head Ztl at pivotedpoints 36 (only one shows in the drawing). The pivotal connections 36may be made, as illustrated, by means of short pivot rods extending fromthe adjacent side Walls of the housing 26 and journaled in the ends ofthe associated pivot arms or by means of a shaft common to the levers32a, 32b and passing through the housing. The primary pivotal connection36 to the combined lifting and spinning head 20 is located relative t-othe center of mass of the head 20 and associated supported components soas to cause the head 20 to exhibit a tendency to turn in acounter-clockwise direction relative to the pivotal con ncction 36.Rotation of the head 20 in counter-clo-ckwise direction is limited,however, by the provision of suitable stops 38 or the like supported onthe side walls of the housing 26 and adapted to underlie and engageabutting surfaces of the pivot levers 32a, 32b. The position of thestops 38 relative to the abutting surfaces is selected to position thevacuum chuck 22 in horizontal abutment with the face f -of picture tubeP, when the pivot levers 32a, 32b are in their lowermost position.

The combined lifting and spinning head 2t), malntained in the abovedescribed angular position relative to the pivotal connections 36 of thepivot levers 32a, 32b is moved along an arcuate path in a clockwisedirection about the main pivot shaft 34 by means of a hydraulic liftmechanism, 42 connected to the pivot levers 32a, 32b. This liftmechanism, of generally known construction, embodies a hydraulic lift.cylinder 44 pivotally supported on the frame 16 and having a pistonhead (not shown) mounted therein for reciprocation. vThe piston headdrives a piston shaft 46 which is pivotally connected to a cross shaft48. Cross shaft 48 is common to the pivot levers 32a, 32b and is placedon the levers at a positlon intermediate the main rocking shaft 34 andthe primary pivotal connection 36.

The lift mechanism 42 is incorporated in a closed hydraulic system, inaccordance with principles and practices Well understood per se. In thediagrammatic and illustrative showing of Fig. l, the cylinder 44 isprovided with appropriate conduits 49a, 49b which alternatively serve asinlets and outlets for the hydraulic iluid. The conduits are connectedto a four-way valve, generally designated by the reference numeral 50,which includes double solenoid controls arranged to alternately permitthe hydraulic fluid to enter the lower conduit 49a, with the upperconduit 49b serving as a fluid outlet, or to permit the duid to enterthe upper conduit 49b, while the lower conduit 49a serves as an outlet,or return to the hydraulic drive system. The double-solenoid controlvalve 50 is operated by a control switch (not shown) arranged at theoperators station 18. The control switch for the hydraulic operatingmechanism 42 may be disposed so that, upon depressing the foot treadle52, the hydraulic uid will enter the conduit 49a and drive the piston 36upwardly to move the pivot levers 32a, 32b clockwise about the pivotshaft 34. This rocking motion will continue until such time as theoperator removes his foot from the foot treadle, whereupon the liftinghead 20 will be held in the position achieved at that instant (i. e.

the coating position of Fig. 3). At a latter time, opera-v tion undercontrol of the foot treadle 52 may be again instituted to allow thehydraulic duid to enter the upperr conduit 49b, returning the combinedlifting and spinning head 20 to the tube pick-up position of Fig. 1. Itis to be expressly understood that the control system 42 is illustrativeand that numerous other systems may be employed. For example, in lieu offoot control by the worker at the operating location 18, the movement ofthe lifting and spinning head 20 may be appropriately coordinated into acompletely automatic system.

In order to turn the combined lifting and spinning head 20 more rapidlyafter the neck of the cathode ray tube blank is lifted clear of thesupport 12a, lost-motion linkages 54 are connected between the combinedlifting and spinning head 20 and the frame 16. In the illustrativeernbodiment, a pair of sliding links are provided on either side of thehousing 26, the linkages being arranged to pass outwardly of the pivotlevers 32a, 32b. These links are pivavea-sto bted at one end on thepivot shaft 56 which extends transversely of the frame 16 above thepivot arm-pivot shaft 34: The opposite ends of the sliding links arepivoted on the housing 26 by means of link pivot shafts 58 which, asseen in Fig. 1, are offset from the pivot `arm pivot points 36. Each ofthe lost-motion linkages includes two slidably interconnected sectionswhich cooperate, when not extended, to apply a turning movement to thelifting and spinning head 20, effective to cause rotation of the headabout` the pivot points 36. The interconnections between the sections54a, 54b of the collapsible links 54 are made by pins on the sections54a received and free to travel within appropriate longitudinal slots onthe sections 54b. The resulting structure produces a` motion of the headwhich is the result of the pivot points 36 travelling along one arc,defined by the pivot arms 32a, 32b, and the link pivot points 58travelling along another arc defined by the collapsed length of thesliding linkages 54.

Other types of lost-motion devices may be employed to effect delayedrotation of the head about its pivot points, the key requirement beingthat, after a given amount of travel of the head along an arc such asthat provided by the pivot arms 32a, 32b, the head is then rotated aboutthe pivot points 36 so as to increasethe effective rate of rotation ofthe head away from its position of rest at the loading station. Suchlost-motion devices would include, for example, guide surfaces supportedon either side of the head by suitable arms projecting from the standard16. The guide surfaces would provide a track against which the linkpivot shafts 58 would come to bear as the head was raised, and thenwould slidably guide the link pivot shafts along a prescribed path, asfor example, a path having afixed-radius of curvature about the point onthe frame 16 presently occupied by the pivot shaft 56.

In any case, the location of the pivot shaft 58 on the head ismadeconsidering the rate of turn of the head desired, and the action of thelost-motion device on the pivot shaft. In the illustrative embodiment,the rate of turn of the head 20 about the pivot points 36 is an inversefunction (for any given rate of lift of the pivot arms 32a, 32b) of thedistance between pivot points 36 and pivot shaft 58.

In the illustrative example, when the lifting and spinning head is inthe loading position of Fig. l, the lostrnotion linkages 54 are inclinedat an angle of approximately with the horizontal. As the piston 46 ofthe hydraulic operating mechanism 42 drives the levers 32a, .32bclockwise about the shaft 34, the head 20 is carried along withoutrotation about the pivot points 36. When 'the collapsible linkages 54are carried to an approximately horizontal position, the respectivelinkage sections 54a, 54b are completely collapsed. At this point thehead 20 is tilted at an angle of aproximately 20 from the vertical andthe depending neck n of the tube P has cleared the cradle-like support12a. During the further travel of the pivot arms 32a, B2b through anangle of about 10, the lifting and spinning head 20 is turned about thehead pivots 36 as a result of pressure applied to the link pivots 58 bythe linkages 54. In the illustrative example, the entire throw of thepivot arms a, 30b is approximately 30, and the head 20 is pivoted to anangular olset position of approximately with respect to the vertical.Thus the picture tube blank is raised to the proper level and placed atthe proper angle for the coating operation incident to contact with thesupport 12.

ln order to axially spin the suction chuck 22 with the picture tube Psupported thereon, a suitable drive motor 60 is supported on the movablehead 20 and coupled to the drive shaft, as by the chain and sprocketdrive 62. The motor is intermittently energized by circuitry (not shown)to etect spinning of the supported tube when in the coating position,the occurrence and duration of spinning being under control of theoperator-as by foot conduit 29 appropriately coupled to the shaft 24.The

picture tube lifting operation is then instituted by further depressingthe foot treadle 52 which, through the fourway solenoid control valve50, applies hydraulic pressure to the lowerend of the cylinder 44 todrive thepiston shaft 46 upwardly. During the rst interval of turn` of`the head 20 about the primary rocking shaft 34, and while thelost-motion is allowed by the linkages 54, the head 20 remains in itsoriginal position relative to the pivot arms 32a,` 32b. After arrivingat the clearance positionof Fig. 2, movement of the pivot arms undercontrol ofthe operating mechanism 42 continues and the head 2t) beginsto turn about the pivots 36 and relative to the pivotarms.` When thehead2() reaches the tube coating position of Fig. 3, release of the foottreadle 52 interrupts the lifting motion and holds 'the tube iirmly inplace. Thereupon, the operator, by depressing a further foot treadle orthe like, causes axial spinning of the supported picture tube P aboutthev axis of the shaft 24. When the coating operation is completed,spinning may be interrupted and theprocessed tube returned to thesupportlZa ofthe conveyor 12 by again depressing the foot treadle S2,releasing the pivot arms and returning the tube blank to the bulbcarriage. When the coated tube blank has been restored to thesupport 12awith the appropriate coating thereon, the treadle 52 may be againoperated to cause release of the tube P preparatory to indexing of theconveyor 12 t-o bring a further tube to the coating station 10.

What is claimed is:

l. In a picture tube processing machine, a support for accommodating apicture tube with the tube face uppermost, a head movable toward andaway from said support, a vacuum chuck mounted on said head for axialrotation and engageable with said tube face in response to movement ofsaid head toward said support, means for developing a suction forcewithin said vacuum chuck when engaging said tube face, operating meansconnected to said head for moving said head away from said supi port andinto a work position wherein the interior of said tube is accessible,and a drive including control means for periodically causing axialrotation of said vacuum chuck.

2. The combination with a conveyor including supports for moving apicture tube `to a coating station, of tubewl-ifting and spinningmechanisms at said coating station for sequentially removing saidpicture tube from said support and imparting axial rotation to saidpicture tube, said mechanism including a head, a vacuum chuck includingan elastomer gripping cup engageable axially of said picture tube, ahollow shaft fixed axially of and in communication with said vacuumchuck and mounting the latter on said head for spinning movement aboutan axis coinciding with the tube axis, means coupled to said hollowshaft for developing a partial vacuum within said vacuum chuck,actuating means on said head operatively connected to said hollow shaftfor periodically spinning said vacuum chuck, and operating meansconnected to said head for moving the latter to a Work position.

3. A station for applying a conductive coating to the inner walls of apicture tube having a picture face and a neck terminating in an open endcomprising a cradlelike support accommodating. a picture tube ininverted This operates` a solenoid valve and connects the` areaal@condition, an assembly movable along a predetermined path for liftingsaid picture tube from said support and displacing said picture tube toan inclined position wherein the inner walls of said picture tube areaccessible through the open end yof said neck, said assembly including avacuum chuck engageable against said tube face axially of said tube, ahollow shaft in communication with and mounting said vacuum chuck forrotation coaxially of said picture tube, means coupled to said hollowshaft for developing a partial vacuum within said vacuum chuck, andactuating means operatively connected to said assembly for moving samealong said predetermined path, said actuating means including a standardadjacent to said support, and a lever arm turning on said standardhaving a pivotal connection to said assembly, a lostmotion linkageinterposed between said standard and said assembly, andv driving meansoperatively connected to said lever arm.

4. In a picture tube coating station, tube handling mechanisms forpicking up a picture tube and moving said picture tube to a coatingposition, said picture tube handling mechanisms including a vacuum chuckadapted to beconnected to exhausting means, and a head supporting saidvacuum chuck and moving with it in cornpound rotational movement duringmovement into said coating position, a lever arm swingable about a trstaxis on said station and pivotably connected to said head, a lost-motiondevice on said station having a connection to said` head, saidlost-motion device being elective to turn said head relative to saidlever arm after movement of said lever arm through a predetermined arc.

5. An article handling device for lifting an article from a support by acompound movement comprising a Work holder adapted for engagement withsaid article, a lifting head attached in tixed relationship to said workholder, a standard, a linkage pivotly attached at one end to saidstandard and pivotly attached at the other end to said head forimparting arcuate displacement of the article from the support, and anarm pivotly attached to linkage and pivotly attached to said headvertically above said linkage for imparting a second arcuatedisplacement of the article from the support.

6. Anarticle handling device for liftingan article from a support yby acompound movement comprising a work holder adapted for engagement withsaid article, a lifting head aixed to Vsaid work holder, means mountedupon said head for axially rotating said work holder, a linkage pivotlyconnected to said head for imparting an arcuate displacement of thearticle from the support, and an arm pivotly connected to said head forimparting a second arcuate displacement of the article from the support.

7. An article handling device for lifting an article from a support by acompound movement comprising a work holder adapted for engagement withsaid article, a lifting head attached to said work holder in fixedrelationship, controllable means mounted on 'said head for `axiallyrotating said work holder, a standard, an actuating device affixed atone end to the standard, a slidable linkage pivotly attached at one endto said standard and at the opposite end to said head for impartingarcuate displacement of the article from the support, and a bell cranklever, one point of said crank being pivotly attached to said standard,a second point of said crank being pivotly attached to the other end ofsaid actuating device, and the third point of said crank being pivotlyattached to said lifting head for imparting further arcuate displacementof the article from the support.

References Cited in the le of this patent UNITED STATES PATENTS BaileyJuly 7, 1953

